In the line "with low ‘r camping", the 'r stands for or. I did the 'r to make it flow smoother and to make the distinction between the two less obvious. But they ARE separate. "with low or camping". This is the line that the language tag applies to.

Hint 2

The first 4 lines are about the word, the "I'm often confused.." is to tell that the next 3 lines are mistaken words (homophones/mispellings) for it.

Hint 3

First 2 lines refer to 2 pokemon. The next 2 can be taken separately. The last 2 lines can be taken separately as well.

Hint 4 - updated

One of the answers below is almost there, they are just slightly missing the mark. If it's partially correct...then what must the other parts be?

$\begingroup$Good guess, but not quite. Some things don't fit right, I'm not sure how the belie line would allude to your suggestion. I could see why you would think that for the pokemon line, but that would be whole, not part ^-^$\endgroup$
– SensorayMar 26 at 4:35

$\begingroup$You're getting close though, you have some of the pieces, you just gotta put them together right :]$\endgroup$
– SensorayMar 27 at 13:14

I'm going to build off of other people's answers here and take a guess:

Meowth

Part pokemon am I, or perhaps two,

mew and mewtwo definitely fit the bill here, but you're only using 'me'. It is only a part of both these pokemon. So 'Me' is the first part of the name.

But not to belie, what I think of you.

Someone mentioned the really common question "What does your cat think of you?". Meowth is a cat.

I’m often confused,

with low ‘r camping

Here we're basically building the second part of the name. low is an anagram for owl, and an h looks like a stake used to put up a camping tent. This is only partly complete, so we have 'owlh'.

Or expressly used,

when overbar adding.

I'm a bit thrown off here because I can't separate the two lines, when in your 3rd hint you mention that they can be taken separately. But adding the overbar onto the 'l' character will make a 't', so all in all we get 'owth'

In conclusion:

'me' + 'owth' = Meowth!

edit :

I guess the 3rd hint also throws me off about the second 2 lines and how they are separate, but I'm pretty sure I got the correct answer in the end anyways.

$\begingroup$Nice attempt, but this is not the answer. Some of your guess were very reaching, but everything will fit in nicely with the right word. I thought your idea about the overbar and I was really creative, but that's not it. Keep thinking!$\endgroup$
– SensorayApr 4 at 14:06

Here we have a pokemon that shares part of his name with others (slowpoke, slowbro). He also has a shellder attached to his head, which might be what the two is referencing.

But not to belie, what I think of you.

This is the only line I'm having trouble fitting into this. I'll make a crazy pitch and say it has something to do with slowking being really intelligent due to the shellder injecting venom into him, so maybe this is like he's being condescending or something.

I’m often confused, with low ‘r camping

Both words that sound a lot like parts of slowking's name.

Or expressly used, when overbar adding.

Perhaps the overbar here is the shellder being 'added' to his head.

If i'm not correct, could you possibly add a hint saying whether the answer is a pokemon or not? I'm assuming based on the title and the first two lines, but if it isn't, then it might not be obvious enough.

$\begingroup$Make sure to carefully read the hints, and perhaps the comments on other posts. Your idea with the 2 part pokemon is creative and I like it! But this is not the correct answer.$\endgroup$
– SensorayApr 4 at 18:50